suppose interstate define 2 : 3.5 current of Primary is about 35ma voltage of 200 (7VA)
Can I use main transformer that I have on hands which primary of 220V and secondary of 380V - 0 - 380 200mA?
it is almost the same ratio 220V primary : 385V secondary (close to 380V).
Can I use main transformer that I have on hands which primary of 220V and secondary of 380V - 0 - 380 200mA?
it is almost the same ratio 220V primary : 385V secondary (close to 380V).
I have not used transformers this way but some on the forum have.
If it's a toroidal transformer you can think about it. If not, the word is don't bother.
There are lots of posts on diyAudio about this. One search result here.
It will work in Push-Pull with well balanced circuit.
If single ended you need to use a parallel feed (aka parafeed) topology because the core of a typical power transformer is not gapped for DC.
I don't know if your power transformer will have enough inductance to support frequencies as low as you want.
Also the 380-0-380 winding gives ratio of 220:760 so your desired ratio means you use one half of the 380-0-380 winding (either the 380-0 end or 0-380).
hope this helps until the cavalry arrives
If it's a toroidal transformer you can think about it. If not, the word is don't bother.
There are lots of posts on diyAudio about this. One search result here.
It will work in Push-Pull with well balanced circuit.
If single ended you need to use a parallel feed (aka parafeed) topology because the core of a typical power transformer is not gapped for DC.
I don't know if your power transformer will have enough inductance to support frequencies as low as you want.
Also the 380-0-380 winding gives ratio of 220:760 so your desired ratio means you use one half of the 380-0-380 winding (either the 380-0 end or 0-380).
hope this helps until the cavalry arrives
While some think it works "okay " and if they do good luck to them , personally I don't hold that opinion and would rather use a "made for the job " genuine audio transformer .
JLH in his book points out the flaws in mains transformers.
Here is general comment on mains transformers themselves written in easy to understand wording ( no university level algebra ) -
Power Transformers for Audio Equipment | audioXpress
I am sure many here will say go ahead and quote previous DIY Audio threads ---but not me.
Once you get into the actual manufacturing science of transformers usually shown along with mountains of algebra it doesn't look so good.
JLH in his book points out the flaws in mains transformers.
Here is general comment on mains transformers themselves written in easy to understand wording ( no university level algebra ) -
Power Transformers for Audio Equipment | audioXpress
I am sure many here will say go ahead and quote previous DIY Audio threads ---but not me.
Once you get into the actual manufacturing science of transformers usually shown along with mountains of algebra it doesn't look so good.
Toroidal mains transformers can work very well depending on a few things, one being low source impedance (Triode), and as said, they must be used with a push pull config or be used in parafeed since they are not gapped. I have built 10 amps over the last few years that all used Triad toroid power transformers for the output transformers. If you want good LF response, you must interleave a pair of them as in the attached artwork. If someone from Triad is reading this, a 240/480V dual primary would be nice!
EI transformers will NOT work satisfactorily for audio.
The main problem using even a toroidal mains transformer for interstage is the size of it. even if it is up to the job. Still, a 25VA 1:1 toroid costs 25$, but a 1:1 interstage built for audio costs 100$. It all depends on the length you want to go for either audio quality, or cost savings.
EI transformers will NOT work satisfactorily for audio.
The main problem using even a toroidal mains transformer for interstage is the size of it. even if it is up to the job. Still, a 25VA 1:1 toroid costs 25$, but a 1:1 interstage built for audio costs 100$. It all depends on the length you want to go for either audio quality, or cost savings.
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I am sorry to ask this question.
Normally power transformer is not gapped.
Can you help me draw picture of 2 transformer one is gapped anotheer is not gapped.
Thank you and sorry to bother for gapped topic. I really can't imagine it
Normally power transformer is not gapped.
Can you help me draw picture of 2 transformer one is gapped anotheer is not gapped.
Thank you and sorry to bother for gapped topic. I really can't imagine it